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Old 07-11-2020, 02:00 PM   #30 (permalink)
Join Date: Mar 2020
Location: Quebec Qc Canada
Posts: 52

AcuraMatata - '99 Acura EL Base
90 day: 36.2 mpg (US)

Le Vehicle - '12 Dodge Gran Caravan SE
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Rear wheels boat tails

As seen on “Aerocivic” and some other ecomodded cars, rear wheel boat tails may help in car fuel economy. In the end, small economies a make large economy. So, I decided to try some.

I had some vinyl corners that were used as airplane type vortex generators and I had some vinyl gutter leftover from the side skirts fabrication.

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The vinyl corners were first attached to the rear part of the belly pan with self tapping screws.

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The boat tail is made. Note that the front of the boat tail is angled so that when installed air moved by wheel is deflected under the car. Also, note that the rear part of the boat tail will be opened like the no bottom box concept used on car rear ends.

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The boat tail is attached to the corners support with self tapping screws on both sides. Et voilą!

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For constant throttle opening of 17,65 %, the average top speed increase is 4,3 Km/h from 110,7 Km/h. A 3 % average top speed increase at 18,43 % to reach about 116 Km/h.

Now fuel economy. That is what we are here for! The Boat tails behind the rear wheels seem to reduce fuel consumption by about 1 L/100 km or a 20 % mileage improvement at speeds between 100 and 120 Km/h. That is what the data says!

See many mods in detail with results on my modification thread for my 1999 Acura EL, similar to US Civic EX

Facts, please, give me the facts! Theoretical knowledge is verified by empirical knowledge! Check Einstein's General Relativity Theory E=MC^2! Every few years some new astrophysics observation and data prove some of Einstein's theory predictions more than a century old.

Last edited by ACEL; 07-11-2020 at 05:49 PM.. Reason: To complete
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California98Civic (07-11-2020)